I. Field of the Invention
This invention relates generally to stone cutting apparatus and more particularly to the design of a machine for forming a true, precision, straight-line edge across the exposed surface of a slab of granite or other stone.
II. Discussion of the Prior Art
In forming stone plaques, monuments, headstones, etc., a slab of marble, granite or other suitable stone is first roughly cut to substantially the desired size and, subsequently, one or more surfaces of the block are smoothed and polished to yield a desired ornamental appearance. Because the cutting step leaves a somewhat rough edge on the perimeter of the polished surfaces, it is desirable to shape the stone so as to provide the finished surface with a precision straight-line edge around its periphery.
From time immemorial, the edging of decorative stones used as monuments has been a manual operation. Experienced stone cutters, using a scribe and a hammer and chisel have meticulously chipped the stone along a desired line proximate the rough edge to achieve the desired border appearance. This hand operation is quite costly, being labor intensive and slow. Furthermore, months of apprenticeship training are usually required before a person is able to perform the operation without producing excessive rejects. To my knowledge, no one has heretofore devised a machine for obviating this hand labor.
I am aware of various prior art patents relating to stone cutting machines. My own earlier U.S. Pat. Nos. 3,727,600 and 2,912,970, describe machines useful in rough-cutting stone blocks prior to any finishing steps. Furthermore, I am aware of the U.S. Pat. Nos. 3,677,258; 3,756,216; and 3,809,049, each of which is assigned to the H. E. Fletcher Company of Westford, Mass. For the most part, the above-mentioned Fletcher Patents were granted on various changes made to stone cutting machines which were designed, developed and manufactured by the assignee of the present invention. Again, none of these patents describe a machine which will provide a desired straight-line, precision edge to a block of stone and thereby replace the manual chipping operation performed by skilled artisans.